The invention pertains to a device for the separation of solid materials from a stream of liquid, consisting of a pipe shaped housing at the interior wall of which there is a preferably funnel shaped filter which with its tip points in the direction of the flow, and at the upstream side a rotating suction device running at an angle to the surface line of the filter and an axially mounted suction rotor at the end of which, in the direction of the flow, provisions are made for a suction opening.
From European Patent 0225 401 a filter is known which features a funnel shaped screen and a hydraulic rinsing device. The filter has proven successful in the case of coarse grained contaminants, but it has the disadvantage that fibrous contaminants are often pressed, due to the spray jets, against the filter surface at the discharge side and that they do not separate from the filter surface.
In German Patent 36 40 638 a filter is known in the case of which the filter is subdivided into individual sectors. Coarse grained contaminants can be drawn off without any problems. For economical reasons, the quantity to be drawn off cannot be increased arbitrarily, so that, especially in the case of larger filters due to the large sectors, the suction velocity in the filter perforation is often insufficient to remove fibrous contaminants from the filter surface and to carry them off.
The filter of published German patent application 38 29360 is well suited for fibrous contaminants, but in the case of coarse grained contaminants it can happen that these get caught between the filter and the rotating suction device block the latter.